THE EFFECT OF GREEN TEA EXTRACT - EPIGALLOCATECHIN GALLATE (EGCG) ON PORCINE OVARIAN GRANULOSA CELL

Abstract

The aim of our study was to elucidate the potential effect of green tea substance on basic ovarian functions. For this purpose, we examined the action of green tea bioactive molecule, epigallocatechin gallate (given at doses 0, 1, 10, 100 μg/mL), on cultured porcine ovarian granulosa cell functions - proliferation, apoptosis and steroidogenesis. Accumulation of PCNA (marker of proliferation), BAX (marker of apoptosis) and the release of steroid hormones (progesterone and testosterone) were analysed by immunocytochemistry and RIA respectively. It was observed that epigallocatechin gallate addition decreased the percentage of proliferative (PCNA-positive) cells at all used doses (1, 10 and 100 μg/mL). The percentage of apoptotic (BAX-positive) cells was increased at the highest used dose (100 μg/mL), but not a lower doses. Epigallocatechin gallate stimulated progesterone release (at 10 μg/mL but not at 1 and 100 μg/mL) and diminished testosterone release (at 1 μg/mL but not at 10 and 100 μg/mL) by porcine granulosa cells. Our results suggest a direct effect of epigallocatechin gallate on proliferation, apoptosis and steroidogenesis in porcine ovaries. Taken together, these data suggest that green tea molecule epigallocatechin gallate can negatively affect reproductive (ovarian) functions – suppress ovarian cell proliferation, promote their apoptosis and alter release of steroid hormones.